fixed: give dtol in LinSolParams a more sane default.

this is the criteria used by petsc to detect a divergent solution process,
i.e. the maximum relative increase in the residual before the process is
stopped. we now allow 3 orders of increase

git-svn-id: http://svn.sintef.no/trondheim/IFEM/trunk@852 e10b68d5-8a6e-419e-a041-bce267b0401d

src/LinAlg/LinSolParams.C

@@ -32,7 +32,7 @@ void LinSolParams::setDefault ()
 
   atol   = 1.0e-6;
   rtol   = 1.0e-6;
-  dtol   = 1.0e-6;
+  dtol   = 1.0e3;
   maxIts = 1000;
 #endif
 }